In politics, winning the argument matters. Often it is impossible to determine exactly who has won the argument, but MPs do look at the evidence and they do change their minds. Which is why Case Not Made (pdf), a report from the leftwing pressure group Compass, could be significant. Lord Mandelson is justifying his plans for the partial privatisation of the Royal Mail entirely on the findings of the 167-page Hooper report published in December. In Case Not Made, Compass tries to show that Hooper was wrong.

In his introduction, Neal Lawson, the chair of Compass, says:

Royal Mail is simply not the failed and failing organisation portrayed in the Hooper report. Furthermore, the European comparators [Richard] Hooper uses, most notably Germany and the Netherlands, are not the shining examples of efficiency he claims. The German system is profitable because it charges its customers more, not because it is more efficient. The Dutch system derives its "efficiency" on the basis of an operation in a small, flat country. Our Royal Mail is not just the lowest priced service in the EU but is also still profitable.

Case Not Made claims that:

• 88% of Royal Mail revenues are from activities that are price-controlled. The equivalent figure for Deutsche Post (DP), its German counterpart, is just 37%

• The UK has 6% more post boxes than Germany (115,000 instead of 109,000), despite having a population that is 25% smaller

• Many European postal services only deliver five days a week, not six

• The Royal Mail delivers 153 items per employee, the same as its Dutch counterpart TNT. DP manages 187 items per employee

• The cost to the Royal Mail of delivery is 27p per item. The equivalent figure for DP is 40p and TNT 43p.

Commenting on Case Not Made, the Labour MP John Grogan said: "This critique of the Hooper report will alarm all Labour MPs. There are clearly no grounds for the part-privatisation of Royal Mail. We need a dynamic alternative but within the public sector."